Pinning down the location of a jar file

[Greg Jewell]

Hi All,

I have a class inside a jar that wants to read the containing jar's manifest. Given that I don't know where on the machine the jar will be placed, I don't know how to instantiate a JarFile object. How do I determine the location of the jar in order to get a JarFile or JarURLConnection object?


Thanks,
Greg Jewell

[Petr Blahos]

 
package my.package.jar;
 
import java.net.*;
 
public class JJJ {
public static void main(String[]args) {
URL url = ClassLoader.getSystemClassLoader().getResource("my/package/jar");
System.out.println(url);
}
}

The output of this is:

jar:file:/D:/cygwin/home/petr/java/jar/jjj.jar!/my/package/jar


I hope it will help.

Petr

[Petr Blahos]

Oh, BTW there is a _VERY_ nice article starting with class loader
explanation, going on through reflection to runtime code generation:

http://www-106.ibm.com/developerworks/java/library/j-dyn0429/

Enjoy!
P.

[Greg Jewell]

Thank you very much, Petr. This is exactly what I was looking for.